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1.
PLoS Biol ; 21(8): e3002246, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37651352

RESUMO

The convolution of membranes called cristae is a critical structural and functional feature of mitochondria. Crista structure is highly diverse between different cell types, reflecting their role in metabolic adaptation. However, their precise three-dimensional (3D) arrangement requires volumetric analysis of serial electron microscopy and has therefore been limiting for unbiased quantitative assessment. Here, we developed a novel, publicly available, deep learning (DL)-based image analysis platform called Python-based human-in-the-loop workflow (PHILOW) implemented with a human-in-the-loop (HITL) algorithm. Analysis of dense, large, and isotropic volumes of focused ion beam-scanning electron microscopy (FIB-SEM) using PHILOW reveals the complex 3D nanostructure of both inner and outer mitochondrial membranes and provides deep, quantitative, structural features of cristae in a large number of individual mitochondria. This nanometer-scale analysis in micrometer-scale cellular contexts uncovers fundamental parameters of cristae, such as total surface area, orientation, tubular/lamellar cristae ratio, and crista junction density in individual mitochondria. Unbiased clustering analysis of our structural data unraveled a new function for the dynamin-related GTPase Optic Atrophy 1 (OPA1) in regulating the balance between lamellar versus tubular cristae subdomains.


Assuntos
Aprendizado Profundo , Membranas Mitocondriais , Humanos , Mitocôndrias , Aclimatação , Algoritmos
2.
Hum Mol Genet ; 32(9): 1524-1538, 2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-36611008

RESUMO

Drosophila is an excellent model organism for studying human neurodegenerative diseases (NDs). However, there is still almost no experimental system that could directly observe the degeneration of neurons and automatically quantify axonal degeneration. In this study, we created MeDUsA (a 'method for the quantification of degeneration using fly axons'), a standalone executable computer program based on Python that combines a pre-trained deep-learning masking tool with an axon terminal counting tool. This software automatically quantifies the number of retinal R7 axons in Drosophila from a confocal z-stack image series. Using this software, we were able to directly demonstrate that axons were degenerated by the representative causative genes of NDs for the first time in Drosophila. The fly retinal axon is an excellent experimental system that is capable of mimicking the pathology of axonal degeneration in human NDs. MeDUsA rapidly and accurately quantifies axons in Drosophila photoreceptor neurons. It enables large-scale research into axonal degeneration, including screening to identify genes or drugs that mediate axonal toxicity caused by ND proteins and diagnose the pathological significance of novel variants of human genes in axons.


Assuntos
Proteínas de Drosophila , Doenças Neurodegenerativas , Animais , Humanos , Drosophila/genética , Drosophila/metabolismo , Doenças Neurodegenerativas/metabolismo , Axônios/metabolismo , Neurônios/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo
3.
J Neurosci ; 42(24): 4937-4952, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35534228

RESUMO

In human neurodegenerative diseases, neurons undergo axonal degeneration months to years before they die. Here, we developed a system modeling early degenerative events in Drosophila adult photoreceptor cells. Thanks to the stereotypy of their axonal projections, this system delivers quantitative data on sporadic and progressive axonal degeneration of photoreceptor cells. Using this method, we show that exposure of adult female flies to a constant light stimulation for several days overcomes the intrinsic resilience of R7 photoreceptors and leads to progressive axonal degeneration. This was not associated with apoptosis. We furthermore provide evidence that loss of synaptic integrity between R7 and a postsynaptic partner preceded axonal degeneration, thus recapitulating features of human neurodegenerative diseases. Finally, our experiments uncovered a role of postsynaptic partners of R7 to initiate degeneration, suggesting that postsynaptic cells signal back to the photoreceptor to maintain axonal structure. This model can be used to dissect cellular and circuit mechanisms involved in the early events of axonal degeneration, allowing for a better understanding of how neurons cope with stress and lose their resilience capacities.SIGNIFICANCE STATEMENT Neurons can be active and functional for several years. In the course of aging and in disease conditions leading to neurodegeneration, subsets of neurons lose their resilience and start dying. What initiates this turning point at the cellular level is not clear. Here, we developed a model allowing to systematically describe this phase. The loss of synapses and axons represents an early and functionally relevant event toward degeneration. Using the ordered distribution of Drosophila photoreceptor axon terminals, we assembled a system to study sporadic initiation of axon loss and delineated a role for non-cell-autonomous activity regulation in the initiation of axon degeneration. This work will help shed light on key steps in the etiology of nonfamilial cases of neurodegenerative diseases.


Assuntos
Proteínas de Drosophila , Doenças Neurodegenerativas , Animais , Axônios/fisiologia , Drosophila/fisiologia , Proteínas de Drosophila/genética , Feminino , Sinapses/fisiologia
4.
Cancer Immunol Immunother ; 70(1): 177-188, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32666260

RESUMO

T cell-dependent bispecific antibody (TDB)-induced T cell activation, which can eliminate tumor cells independent of MHC engagement, is expected to be a novel breakthrough immunotherapy against refractory cancer. However, the mechanism of action of TDBs has not been fully elucidated thus far. We focused on TDB-induced T cell-tumor cell contact as an important initial step in direct T cell-mediated tumor cell killing via transport of cytotoxic cell proteases (e.g., granzymes) with or without immunological synapse formation. Using an anti-EGFR/CD3 TDB, hEx3, we visualized and quantified T cell-tumor cell contact and demonstrated a correlation between the degree of cell contact and TDB efficacy. We also found that cytokines, including interferon-gamma (IFNγ) and tumor necrosis factor-alpha (TNFα) secreted by activated T cells, damaged tumor cells in a cell contact-independent manner. Moreover, therapeutic experiences clearly indicated that hEx3, unlike conventional anti-EGFR antibodies, was effective against colorectal cancer (CRC) cells with mutant KRAS, BRAF, or PIK3CA. In a pharmacokinetic analysis, T cells spread gradually in accordance with the hEx3 distribution within tumor tissue. Accordingly, we propose that TDBs should have four action steps: 1st, passive targeting via size-dependent tumor accumulation; 2nd, active targeting via specific binding to tumor cells; 3rd, T cell redirection toward tumor cells; and 4th, TDB-induced cell contact-dependent (direct) or -independent (indirect) tumor cell killing. Finally, our TDB hEx3 may be a promising reagent against refractory CRC with an oncogenic mutation associated with a poor prognosis.


Assuntos
Anticorpos Biespecíficos/imunologia , Carcinogênese/imunologia , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/terapia , Mutação/imunologia , Linfócitos T/imunologia , Animais , Linhagem Celular Tumoral , Citocinas/imunologia , Receptores ErbB/imunologia , Feminino , Células HCT116 , Células HT29 , Humanos , Imunoterapia/métodos , Interferon gama/imunologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Prognóstico , Fator de Necrose Tumoral alfa/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
5.
J Chem Phys ; 152(10): 104105, 2020 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32171211

RESUMO

Several different types of density functional theory (DFT) exchange correlation functionals were applied to a periodic boundary condition (PBC) system [carbon monoxide (CO) adsorbed on Cu(111): CO/Cu(111)] and the differences in the results calculated using these functionals were compared. The exchange correlation functionals compared were those of Perdew-Burke-Ernzerhof (PBE) and those of long-range corrected density functional theory (LC-DFT), such as LC-ωPBE(2Gau) and LC-BLYP(2Gau). Solid state properties such as the partial density of states were calculated in order to elucidate the detailed adsorption mechanisms and back-bonding peculiar to the CO/Cu(111) system. In addition, our benchmark analysis of the correlations among the orbitals of CO and Cu metal using LC-DFT reasonably was in line with the experimentally observed adsorption site. The computation time was reasonable, and other numerical results were found to agree well with the experimental results and also with the theoretical results of other researchers. This suggests that the long-range Hartree-Fock exchange integral should be included to correctly predict the electronic nature of PBC systems.

6.
Molecules ; 25(18)2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32906699

RESUMO

In this study, we investigated the impact of GD1a-expressing bacterial strains on the infectivity of murine norovirus (MNV). Eligible bacterial strains were screened from a sewage sample using flow cytometry, and their genetic sequences of 16S rRNA were determined. The enzyme-linked immunosorbent assay (ELISA) was employed to analyze the binding between bacteria and MNV particles, and the plaque assay was used to assess the effects of GD1a-positive and negative strains on MNV infectivity. The result from ELISA shows that MNV particles are able to bind to both GD1a-positive and negative bacterial strains, but the binding to the GD1a-positive strain is more significant. The infectivity assay result further shows that the MNV infectious titer declined with an increasing concentration of GD1a-positive bacteria. The addition of anti-GD1a antibody in the infectivity assay led to the recovery of the MNV infectious titer, further confirming that the binding between MNV particles and bacterial GD1a ganglioside compromises MNV infectivity. Our findings highlight the role indigenous bacteria may play in the lifecycle of waterborne enteric viruses as well as the potential of exploiting them for virus transmission intervention and water safety improvement.


Assuntos
Bactérias/genética , Bactérias/metabolismo , Infecções por Caliciviridae/virologia , Gangliosídeos/biossíntese , Interações Hospedeiro-Patógeno , Interações Microbianas , Norovirus , Animais , Modelos Animais de Doenças , Expressão Gênica , Camundongos , Ensaio de Placa Viral
7.
Acta Med Okayama ; 73(3): 189-195, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31235965

RESUMO

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is a recently-discovered autoimmune disorder in which antibodies target NMDAR in the brain. The number of reported cases of anti-NMDAR encephalitis has increased rapidly. Anti-NMDAR encephalitis can be mistakenly diagnosed as psychiatric disorders because many patients present with prominent psychiatric symptoms and visit psychiatric institutions first. Thus, psychiatrists should cultivate a better understanding of anti-NMDAR encephalitis. In this review, we present the mechanisms, epidemiology, symptoms and clinical course, diagnostic tests, treatment and outcomes of patients with anti-NMDAR encephalitis. Furthermore, we discuss the diversity of clinical spectra of anti-NMDAR encephalitis, and demonstrate a differential diagnosis of psychiatric disease from the perspective of psychiatry.


Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato/terapia , Encefalite Antirreceptor de N-Metil-D-Aspartato/diagnóstico , Encefalite Antirreceptor de N-Metil-D-Aspartato/epidemiologia , Diagnóstico Diferencial , Humanos , Transtornos do Humor/diagnóstico
8.
Water Sci Technol ; 79(2): 342-348, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30865605

RESUMO

Contribution of specific interactions between human enteric viruses and wastewater suspended solids on human enteric virus removal by microfiltration was studied. A cross-flow microfiltration system was used with rotavirus HAL1166 and Enterobacter cloacae SENG-6 as the model virus and wastewater suspended solid. Cleavage of rotavirus HAL1166 protein VP4 by trypsin produces the VP8* subunit, which specifically interacts with histo-blood group antigen (HBGA). In the presence of Enterobacter cloacae SENG-6, the trypsin-treated rotavirus concentration reduced with time (R2 > 0.6) compared to the reduction of non-trypsin treated rotavirus. Calculation of the gel/cake layer deposited on the membrane, consisting of Enterobacter cloacae SENG-6 and either trypsin-treated or non-trypsin treated rotavirus HAL1166, revealed that the microflocs consisting of trypsin-treated rotavirus and Enterobacter cloacae SENG-6 have lower porosity and permeability, displaying higher resistance to virus passage through the membrane. The results provide evidence that specific wastewater suspended solids-human enteric virus interaction can contribute to increasing the removal of human enteric viruses by microfiltration.


Assuntos
Enterobacter cloacae/fisiologia , Rotavirus/fisiologia , Águas Residuárias/microbiologia , Microbiologia da Água , Humanos , Tripsina , Eliminação de Resíduos Líquidos , Águas Residuárias/virologia
9.
J Neurosci ; 37(49): 11867-11880, 2017 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-29101245

RESUMO

In the adult mammalian brain, neural stem cells (NSCs) generate new neurons throughout the mammal's lifetime. The balance between quiescence and active cell division among NSCs is crucial in producing appropriate numbers of neurons while maintaining the stem cell pool for a long period. The Notch signaling pathway plays a central role in both maintaining quiescent NSCs (qNSCs) and promoting cell division of active NSCs (aNSCs), although no one knows how this pathway regulates these apparently opposite functions. Notch1 has been shown to promote proliferation of aNSCs without affecting qNSCs in the adult mouse subependymal zone (SEZ). In this study, we found that Notch3 is expressed to a higher extent in qNSCs than in aNSCs while Notch1 is preferentially expressed in aNSCs and transit-amplifying progenitors in the adult mouse SEZ. Furthermore, Notch3 is selectively expressed in the lateral and ventral walls of the SEZ. Knockdown of Notch3 in the lateral wall of the adult SEZ increased the division of NSCs. Moreover, deletion of the Notch3 gene resulted in significant reduction of qNSCs specifically in the lateral and ventral walls, compared with the medial and dorsal walls, of the lateral ventricles. Notch3 deletion also reduced the number of qNSCs activated after antimitotic cytosine ß-D-arabinofuranoside (Ara-C) treatment. Importantly, Notch3 deletion preferentially reduced specific subtypes of newborn neurons in the olfactory bulb derived from the lateral walls of the SEZ. These results indicate that Notch isoforms differentially control the quiescent and proliferative steps of adult SEZ NSCs in a domain-specific manner.SIGNIFICANCE STATEMENT In the adult mammalian brain, the subependymal zone (SEZ) of the lateral ventricles is the largest neurogenic niche, where neural stem cells (NSCs) generate neurons. In this study, we found that Notch3 plays an important role in the maintenance of quiescent NSCs (qNSCs), while Notch1 has been reported to act as a regulator of actively cycling NSCs. Furthermore, we found that Notch3 is specifically expressed in qNSCs located in the lateral and ventral walls of the lateral ventricles and regulates neuronal production of NSCs in a region-specific manner. Our results indicate that Notch3, by maintaining the quiescence of a subpopulation of NSCs, confers a region-specific heterogeneity among NSCs in the adult SEZ.


Assuntos
Células-Tronco Adultas/metabolismo , Ventrículos Laterais/citologia , Ventrículos Laterais/metabolismo , Células-Tronco Neurais/metabolismo , Receptor Notch3/biossíntese , Fatores Etários , Animais , Células Cultivadas , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor Notch3/deficiência
10.
Cancer Sci ; 109(4): 1135-1146, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29444383

RESUMO

The expression of ATP-binding cassette subfamily G member 2 (ABCG2) is related to tumorigenic cancer stem cells (CSC) in several cancers. However, the effects of ABCG2 on CSC-related malignant characteristics in pancreatic ductal adenocarcinoma (PDAC) are not well elucidated. In this study, we compared the characteristics of low (ABCG2-) and high (ABCG2+)-ABCG2-expressing PDAC cells after cell sorting. In adherent culture condition, human PDAC cells, PANC-1, contained approximately 10% ABCG2+ cell populations, and ABCG2+ cells displayed more and longer microvilli compared with ABCG2- cells. Unexpectedly, ABCG2+ cells did not show significant drug resistance against fluorouracil, gemcitabine and vincristine, and ABCG2- cells exhibited higher sphere formation ability and stemness marker expression than those of ABCG2+ cells. Cell growth and motility was greater in ABCG2- cells compared with ABCG2+ cells. In contrast, epithelial-mesenchymal transition ability between ABCG2- and ABCG2+ cells was comparable. In 3D culture conditions, spheres derived from ABCG2- cells generated a large number of ABCG2+ cells, and the expression levels of stemness markers in these spheres were higher than spheres from ABCG2+ cells. Furthermore, spheres containing large populations of ABCG2+ cells exhibited high resistance against anti-cancer drugs presumably depending on ABCG2. ABCG2+ cells in PDAC in adherent culture are not correlated with stemness and malignant behaviors, but ABCG2+ cells derived from ABCG2- cells after sphere formation have stemness characteristics and anti-cancer drug resistance. These findings suggest that ABCG2- cells generate ABCG2+ cells and the malignant potential of ABCG2+ cells in PDAC varies depending on their environments.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas de Neoplasias/genética , Neoplasias Pancreáticas/genética , Antineoplásicos/farmacologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Células-Tronco Neoplásicas/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas
11.
Gastric Cancer ; 19(3): 902-10, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26386560

RESUMO

BACKGROUND: This randomized phase II study compared weekly administration of paclitaxel (wPTX) with the best available 5-fluorouracil (5-FU) regimen as second-line treatment for advanced gastric cancer patients with severe peritoneal metastasis refractory to fluoropyrimidine. METHODS: In the best available 5-FU arm, continuous infusion of 5-FU (800 mg/m(2)/day, days 1-5, every 4 weeks) was given to patients with prior chemotherapy including bolus 5-FU, and methotrexate and 5-FU sequential bolus injection (methotrexate at 100 mg/m(2) followed by bolus 5-FU at 600 mg/m(2) with leucovorin, weekly) was given to those who had previously received continuous infusion of 5-FU or oral administration of fluoropyrimidine. In the wPTX arm, paclitaxel (80 mg/m(2)) was administered on days 1, 8, and 15, every 4 weeks. This study adopted a screening design (one-sided α = 30 %) with the primary end point of overall survival. RESULTS: One hundred patients were randomized to the 5-FU arm (n = 49) or the wPTX arm (n = 51). Although the median survival time was 7.7 months in both arms, the 2-year survival rates were 2.9 % in the 5-FU arm and 9.1 % in the wPTX arm [hazard ratio 0.89 (95 % confidence interval 0.57-1.38), one-sided p = 0.298}. The median progression-free survival was longer with wPTX than with 5-FU [3.7 months vs 2.4 months; hazard ratio 0.58 (95 % confidence interval 0.38-0.88), one-sided p = 0.005]. The incidences of grade 4 neutropenia, grade 3/4 febrile neutropenia, diarrhea, and treatment-related death were 6 %, 4 %, 10 %, and 2 %, respectively, in the 5-FU arm and 2 %, 0 %, 0 %, and 0 %, respectively, in the wPTX arm. CONCLUSIONS: As second-line chemotherapy, wPTX appears feasible and promising. This regimen can be included in a test arm in future phase III trials for treatment of advanced gastric cancer with severe peritoneal metastasis.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Gástricas/tratamento farmacológico , Adulto , Idoso , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Capecitabina/administração & dosagem , Combinação de Medicamentos , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Irinotecano , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Ácido Oxônico/administração & dosagem , Paclitaxel/administração & dosagem , Neoplasias Peritoneais/secundário , Prognóstico , Neoplasias Gástricas/patologia , Taxa de Sobrevida , Tegafur/administração & dosagem
12.
Nano Lett ; 15(5): 3103-8, 2015 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-25807270

RESUMO

We report on an analysis of hot-carrier lifetimes from electron-phonon interaction in lead iodide perovskites using first-principles calculations. Our calculations show that the holes in CsPbI3 have very long lifetimes in the valence band region situated 0.6 eV below the top of the valence band. On the other hand, no long lifetime is predicted in PbI3(-). These different results reflect the different electronic density of states (DOSs) in the valence bands, that is, a small DOS for the former structure while a sharp DOS peak for the latter structure. We propose a reduction of the relaxation paths in the small valence DOS as being the origin of the slow hot-hole cooling. Analyzing the generalized Eliashberg functions, we predict that different perovskite A-site cations do not have an impact on the carrier decay mechanism. The similarity between the DOS structures of CsPbI3 and CH3NH3PbI3 enables us to extend the description of the decay mechanism of fully inorganic CsPbI3 to its organic-inorganic counterpart, CH3NH3PbI3.

13.
Nanotechnology ; 25(24): 245703, 2014 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-24869755

RESUMO

Understanding the role of inter-layer interactions in multi-walled carbon nanotubes is one of the challenges in the design of potential materials because of their large impact on the physical properties of carbon nanotubes. We focused on the thermal properties of double-walled carbon nanotubes (DWCNTs), which are promising materials due to their high durability and thermal efficiency. We investigated the thermal conductance of DWCNTs by using the nonequilibrium Green's function method, and found that the quadratic temperature dependence of the thermal conductance at low temperatures consisted of three regions with different tendencies. Based on analysis of the transmission coefficients and the distribution of the normal modes, the three nonuniform regions were attributed to the energy shifts of the normal modes at the low-energy region. We examined the mechanism of these energy shifts using the coupled vibration model with the parameters from our simulations, and elucidated the multi-wall effects on the thermal transport properties of the nanotube structures. The effects we found demonstrated the significance of tailoring thermal properties to obtain the desired applications.

14.
Hepatol Res ; 44(3): 327-37, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23607695

RESUMO

AIM: We aimed to elucidate the relationship between the contrast enhancement effect of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) on magnetic resonance imaging (MRI) of hepatocellular carcinomas (HCC) and the expressions of hepatocyte transporters (i.e. organic anion-transporting polypeptide [OATP]1B3, multidrug-resistant protein [MRP]2 and MRP3) and to clarify the characteristics of HCC with an MRI high-contrast enhancement effect. METHODS: We retrospectively examined the relationship between the relative enhancement ratio (RER) of HCC, absolute and relative immunohistochemical staining scores of hepatocyte transporters, and histological differentiation of 22 HCC from 21 patients who had undergone preoperative Gd-EOB-DTPA-enhanced MRI. RESULTS: RER had a significant correlation with OATP1B3 expression according to the absolute and relative scores (P = 0.016 vs 0.0006). The RER of HCC with high OATP1B3 and MRP2 expression levels was higher than that of HCC with low OATP1B3 or MRP2 expression levels (P = 0.0003). The RER of HCC with higher OATP1B3 rates was greater than that of HCC with lower OATP1B3 rates (P = 0.0005). HCC histological differentiation showed a significant correlation with OATP1B3 expression and RER (P = 0.023 vs 0.0095). CONCLUSION: We found that coexpression of OATP1B3 and MRP2 influenced the high contrast enhancement of HCC on MRI.

15.
Bioelectromagnetics ; 35(7): 497-511, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25196377

RESUMO

The present experimental study was carried out with rats to evaluate the effects of whole body exposure to 2.14 GHz band code division multiple access (W-CDMA) signals for 20 h a day, over three generations. The average specific absorption rate (SAR, in unit of W/kg) for dams was designed at three levels: high (<0.24 W/kg), low (<0.08 W/kg), and 0 (sham exposure). Pregnant mothers (4 rats/group) were exposed from gestational day (GD) 7 to weaning and then their offspring (F1 generation, 4 males and 4 females/dam, respectively) were continuously exposed until 6 weeks of age. The F1 females were mated with F1 males at 11 weeks old, and then starting from GD 7, they were exposed continuously to the electromagnetic field (EMF; one half of the F1 offspring was used for mating, that is, two of each sex per dam and 8 males and 8 females/group, except for all offspring for the functional development tests). This protocol was repeated in the same manner on pregnant F2 females and F3 pups; the latter were killed at 10 weeks of age. No abnormalities were observed in the mother rats (F0 , F1 , and F2 ) and in the offspring (F1 , F2 , and F3 ) in any biological parameters, including neurobehavioral function. Thus, it was concluded that under the experimental conditions applied, multigenerational whole body exposure to 2.14 GHz W-CDMA signals for 20 h/day did not cause any adverse effects on the F1 , F2 , and F3 offspring.


Assuntos
Encéfalo/efeitos da radiação , Telefone Celular , Campos Eletromagnéticos , Animais , Peso Corporal/efeitos da radiação , Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Comportamento Exploratório/efeitos da radiação , Feminino , Masculino , Exposição Materna , Aprendizagem em Labirinto/efeitos da radiação , Atividade Motora/efeitos da radiação , Tamanho do Órgão , Exposição Paterna , Radiogenética , Radiometria , Ratos Sprague-Dawley , Reprodução/efeitos da radiação
16.
J Chem Phys ; 139(4): 044711, 2013 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-23902007

RESUMO

We study the transport properties of single-walled carbon nanotubes (SWCNTs) using the nonequilibrium Green's function method based on first-principles calculations. We compared three SWCNTs with different chiralities (3, 3), (5, 0), and (4, 2), and found that the thermal conductance varies significantly with the chirality, especially at low temperatures. Such differences are attributed to the dependence on the chirality of the frequency of the lowest optical mode and phonon-phonon interaction with the semi-infinite leads. To obtain accurate low-vibrational frequencies, a force constant correction based on the Lagrange undetermined multiplier method was employed. The phonon-phonon interaction was analyzed in terms of the projection of the phonon coupling with the semi-infinite leads onto the normal modes of the center region. Our result indicates that high optical mode frequency and weak phonon coupling on the armchair (3, 3) SWCNT are the origin of the long quantized plateau found in the experimental thermal conductance.

17.
Jpn J Antibiot ; 66(4): 211-25, 2013 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-24396982

RESUMO

We investigated the susceptibility to antimicrobials of 204 Pseudomonas aeruginosa strains isolated from 21 hospitals in Aichi prefecture from September to November 2009. MIC distributions of various antimicrobials were analyzed in terms of geographic region of isolation, patient status (outpatient or inpatient), and type of specimens that the strain was isolated from. The results were as follows. 1. Although more than 90% of strains were susceptible to all aminoglycosides and colistin, 80-90% of them were susceptible to beta-lactams and fluoroquinolones. MIC distributions of all antimicrobials measured were not significantly different between regions. 2. Only 1 strain (0.5%) was multi-drug resistant Pseudomonas aeruginosa (MDRP). Thirteen strains (6.4%) showed imipenem MIC > or = 16 microg/mL, and 16 strains (7.8%) showed ciprofloxacin MIC > or = 4 microg/mL. These strains tended to be more isolated from urine, respiratory tract specimens, or surgical specimens. 3. The MICs of tazobactam/piperacillin, panipenem, meropenem, doripenem, biapenem, sulbactam/cefoperazone, cefepime, and aztreonam were significantly higher in strains isolated from inpatients than in those from outpatients. MIC distributions of antimicrobials other than beta-lactams were not significantly different between situations where strains were isolated. 4. MIC distributions of piperacillin, all carbapenems, cefepime, gentamicin, and all fluoroquinolones were significantly different among samples from which strains were isolated. The strains isolated from blood showed lower MICs against all antimicrobials than those from other samples. No difference was found in MIC distributions when categorized according to bacteremic origin. The MICs were apparently elevated against beta-lactams, fluoroquinolones, and gentamicin in strains isolated from respiratory tract specimens, and against beta-lactams, and fluoroquinolones in strains isolated from urine. It was suggested that in P. aeruginosa surveillance, the results should be reported by stratifying with patient status, and type of specimens that the strain was isolated from and that regional surveillance should be useful with such stratification to establish antibiograms for empirical antimicrobial choice.


Assuntos
Antibacterianos/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade
18.
Artigo em Inglês | MEDLINE | ID: mdl-36981773

RESUMO

Sensory impairments are common features of autism spectrum disorder (ASD) and are associated with its social impairments. However, there is no established treatment for these impairments in adults with ASD. The Safe & Sound Protocol (SSP) is a listening program designed to improve social communication skills by reducing auditory hypersensitivity. We investigated the effectiveness of the SSP for adults with ASD. We administered the SSP to six participants with ASD aged 21-44 years old, and the effects were assessed using the Social Responsiveness Scale, Second Edition (SRS-2). Secondary outcomes were assessed using the Center for Epidemiological Studies Depression Scale (CES-D), State-Trait Anxiety Inventory (STAI), WHO Quality of Life 26 (WHOQOL-BREF), and Adolescent/Adult Sensory Profile (A/ASP). In this study, only the Social Awareness scale of the SRS-2 Family-Report showed a significant improvement after the intervention. In addition, it was significantly correlated with physical health of WHOQOL-BREF (r = -0.577, p = 0.012), state and trait anxiety of STAI (r = 0.576, p = 0.012; r = 0.708, p = 0.00009, respectively), and CES-D (r = 0.465, p = 0.05). In conclusion, the SSP has a partial effect on social impairments in adults with ASD, specifically on the Social Awareness subscale of the SRS-2.


Assuntos
Transtorno do Espectro Autista , Adolescente , Humanos , Adulto , Adulto Jovem , Transtorno do Espectro Autista/terapia , Transtorno do Espectro Autista/complicações , Projetos Piloto , Qualidade de Vida , Habilidades Sociais , Transtornos de Ansiedade/complicações
19.
Brain Dev ; 45(1): 58-69, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36511274

RESUMO

OBJECTIVE: Bile acid intermediates, 3α,7α,12α-trihydroxycholestanoic acid (THCA) and 3α,7α-dihydroxycholestanoic acid (DHCA), are metabolized in peroxisomes. Some peroxisomal disorders (PDs), such as Zellweger spectrum disorder (ZSD), show an accumulation of bile acid intermediates. In particular, ABCD3 deficiency and acyl-CoA-oxidase 2 deficiency are characterized by these metabolite abnormalities. In patients with ZSD, levels of bile acid intermediates can be lowered by a primary bile acid supplementation treatment; therefore, measuring their levels could help evaluate treatment effectiveness. Here, we established a method for the quantitative determination of bile acid intermediates (THCA/DHCA) for differentiating PDs and assessing bile acid treatment. METHODS: Serum samples, obtained from patients with several forms of ZSD as well as peroxisomal ß-oxidation enzyme deficiencies, were deproteinized and analyzed using liquid chromatography-mass spectrometry. RESULTS: Levels of the bile acid intermediates increased significantly in patients with Zellweger syndrome (ZS) and slightly in patients with neonatal adrenoleukodystrophy and infantile Refsum disease (IRD), reflecting the severity of these diseases. One patient with ZS treated with primary bile acids for 6 months showed slightly decreased serum DHCA levels but significantly increased serum THCA levels. One patient with IRD who underwent living-donor liver transplantation showed a rapid decrease in serum THCA and DHCA levels, which remained undetected for 6 years. In all controls, THCA and DHCA levels were below the detection limit. CONCLUSION: The analytical method developed in this study is useful for diagnosing various PD and validating bile acid treatment. Additionally, it can help predict the prognosis of patients with PD and support treatment strategies.


Assuntos
Transplante de Fígado , Transtornos Peroxissômicos , Síndrome de Zellweger , Recém-Nascido , Humanos , Ácidos e Sais Biliares , Doadores Vivos , Transtornos Peroxissômicos/diagnóstico , Síndrome de Zellweger/diagnóstico
20.
Oncologist ; 17(9): 1163-70, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22622149

RESUMO

BACKGROUND: No standard chemotherapy regimen has been established for unresectable or recurrent small bowel adenocarcinoma (SBA). METHODS: Clinical courses of 132 patients with unresectable or recurrent SBA who received chemotherapy at 41 institutions in Japan were reviewed retrospectively. Patients were classified into five groups according to first-line chemotherapy regimens: fluoropyrimidine monotherapy (group A), fluoropyrimidine-cisplatin (group B), fluoropyrimidine-oxaliplatin (group C), fluoropyrimidine-irinotecan (group D), and other regimens (group E). RESULTS: The number of patients in each group was as follows: groups A, 60 patients; group B, 17 patients; group C, 22 patients; group D, 11 patients; and group E, 22 patients. Median progression-free survival (PFS) times were as follows: group A, 5.4 months; group B, 3.8 months; group C, 8.2 months; group D, 5.6 months; and group E, 3.4 months. Median overall survival (OS) times were as follows: group A, 13.9 months; group B, 12.6 months; group C, 22.2 months; group D, 9.4 months; and group D, 8.1 months. Patients in group C achieved significantly longer PFS times and substantially (but not significantly) longer OS times than patients in group A. After adjusting for clinical background characteristics, fluoropyrimidine-oxaliplatin therapy was a significant positive prognostic factor for PFS and OS times. CONCLUSION: The results suggest that fluoropyrimidine-oxaliplatin combination therapy is the most promising first-line chemotherapy regimen for unresectable or recurrent SBA.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Intestinais/tratamento farmacológico , Intestino Delgado/patologia , Adenocarcinoma/patologia , Idoso , Camptotecina/análogos & derivados , Camptotecina/uso terapêutico , Cisplatino/uso terapêutico , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Intestinais/patologia , Irinotecano , Japão , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Compostos Organoplatínicos/uso terapêutico , Oxaliplatina , Pirimidinas/uso terapêutico , Estudos Retrospectivos
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